Vehicle.



lol

NITED STATES PATENT OFFICE.

JOHN O. MORRIS, 0F DAVENPORT, IOWA, ASSIGNOR, BY MESN ASSIGNMENTS, TO BULLOGK TRACTOR COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION 0F ILLINOIS.

VEHICLE.

Specification of Letters Patent.

Patented June 8, 191.5.

Application filed February 7, 1912. Serial No. 676,02.

the following is a full, clear, concise, and

eXact description, reference being had to the accompanying drawings, forming a part` of this specification.

lvy invention relates to vehicles of that class which employ endless tracks carried by the vehicles and upon. which wheels of the vehicles travel.

My invention has for bnc of its objects the provision of an improved mounting for such tracks whereby they may be automatically adapted to rises and falls on the ground over which the vehicle is passing.

My invention has for another of its ob jects the provision of improved means for arbitrarily adjusting the positions of the tracks so that the tracks may be adapted either to. the normal travel of the vehicle or maybe adjusted to enable the vehicle to turn..

Both objects of any invention are realized in a vehicle. which includes -two tracks, one

upon each side of the vehicle, and which tracks are in the form of chains which are driven by driving sprocket wheels located at the rear of 'the vilains, these sprocket wheels having rims which are interposed between the chain stretches while tension wheels are provided at the forward ends of the chains, these tension lwheels also having rims that are interposed between the chain stretches: Each chain is desirably provided with a truck frame individual thereto, these truck -frames carrying bearings for the 'wheels that are individual to such chain.

By oscillatingly mounting passes, the engagement of the chain with the ground thus substantially imposing no varysince there is no relative motion between the tracks and the ground portions that are actually in engagement with the tracks, a characteristic which is enhanced by so constructing the track chains as to prevent slippage between the same and the round. OW- ing to the extended Contact o the tracks with the ground not only longitudinally ofA the tracks but desirably also ytransversely thereof, zumaimum amount of friction is occasioned between the tracks and the ground when it is endeavored to turn the vehicle from its straight line of travel were it not for the swinging mounting which I have provided for the tracks and the provision of supplemental mechanism coperating with the swinging mounting whereby the tracks may be bodily adjusted so as to be angularly disposed with respect to the ground whereby the area of contact of the tracks with theground is reduced in order to enable the vehicle to be deflected from its course. I do not limit myself to a vehicle having all the characteristics above outlined.

I will explain my invention more fully by reference to the accompanying drawings showing the preferred embodiment thereof and in which- Figure l is a side elevation of a vehicle as it is preferably constructed in accordance with one embodiment of the invention and Fig. 2 is a plan view of the structure as it appears in Fig. l.

Like-parts are'indicated by similar characters of reference through-out the different figures. w

The general type of vehicle illustrated is well known by those skilled in the art. The vehicle illustrated includes a vehicle body ing load upon the track driving mechanism4 1 supported at its forward end by steering novel part of my present invention, I will not fully describe the same. I have employed truck frames 7, one upon each side of the vehicle, these truck frames carrying bearings 8 and 9 for the tension and Y driving wheels and 11. These wheels tread n upon the endless tracks 13 in a manner that will be readily understood, the endless tracks n 1S `being preferably constructed as set forth 1e in my co-pending application Serial No. Q 67 6,021, filed Feb. ,7, 1912.. Each tension wheel 10 is adapted to have its distance from the corresponding driving sprocket wheel 11 adjustably maintained by a tension'adjust- 15 ing device 14 for thepurpose of maintaining the endless track belonging to' these wheels sutliciently taut. Each truck frame 7 is also provided with a carrier l5 in which -a pluralityl of rollers 16 vare mounted, these rollers beingemployed for engaging the upper side of the lower stretch of the associate endlesstrack to maintain the portion of the track between the wheels 10 and 11 sutilciently level so as to prevent the track from unduly conforming with the irregularities in the surface of the ground over which, the vehicle vis moving and to limit the extent to which the lower stretches of the tracks may be upwardly lexed.-

Each truckframe' 7 is provided with a mounting vshaft 17 carried by hangers 18,

' the elements 17 and 18 being preferably located substantially midway betweenthe Wheel bearings 8 and 9. The truck .trame 7 is normally free to oscillate so that either end may be'raised or lowered Jfrom the horizontal position in which the axes ot the wheels 10 and 11 are included as illustrated in Fig. 1, chains 19 and 20 being preferably -t0 employed for defining the range of oscillation of the truck frame. In Fig. 1 the chain 20 is shown as being taut, this condition of the chain 20 being broughtabout when the track-chain is to be-bodily adjusted pre- 4,5 paratory to turning the vehicle.- Normally the chain 20 is slack as isthe chain 1Q. The linksthat compose each track chain'desirably have their external surfaces oi" grip-y ping or holding formation whereby the porwtinof the'ltrack chainresting upon the ground may have firm non-slipping .engagement with the ground. lThe lower ground engaging portion ofthe tracks are' desirablypreventedfrom being raised above the saine plane by means of therollers v16, but

, in order to ermit .these portions-'of the tracks to a apt themselves generally to changing slopes of the ground the swing ing mounting structures 17 and 18 are em- @0 ployed, the truck frames 7, the wheels 10 and 11- carried thereby, as well as the endless tracks being bodily adjusted automatically by the ground as the inclination of l 'the ground varies, the endless tracks and the N coperating parts bodily adjusted'therewith being automatically adjusted with v'respect to the ground without having their .cooperative relationship disturbed.

When .it is desired to turn the vehicle from its straight line course an appreciable degree, I desirably depress the forward ends of the truck frames 7, a result which preferably accomplished by exerting lifting' action upon the rear of the truck frames throught the intermediation of the chains 20. To this end the chains l20, which are secured at their lower ends to theV truck frames 7, are 'attached at their upper endsz to the non-rotating shafts 21 whose upper ends are threaded and have threaded engagement 8e' with sprocket wheels 22 which rotate in f planes that are fixed with resp-ect to the vehicle body 1. The sprocket wheels 22A are. directly driven by sprocket chains 23 that in turn are driven by sprocket pinions 24:. 85 These sprocket pinions 24 are driven by l sprocket chains 25 that in turn are driven j by 'sprocket pinions 26 iixedly mounted upon the shafts 27 of hand operated wheels 2.8.I By the mechanism just described the turn- 90 ing of 'the wheels 28 in one direction will cause the shafts 2l to rise without,rotating whereby the rear ends of the truck frames' 7 are elevated and the forward ends of said truck frames are depressed so that theffor: ward portions of the lower stretches of thev endless tracks will alone.l rest upon 'the ground so that the course ot the vehicle may be changed without the obstructing action which otherwise arises if the rear portions of the lower stretches ci the vendless tracks were not elevated. vAfter the vehicle has been turned the Wheels 28 are reversed in their rotation so that thechains 19 and 20 may both be restored to their normal slack condition. 1 A.

Structures including the rollers 16 not only serve to prevent the upward flexure of the endless tracks but also coperate with the rollers or wheels 16 at the forward ends of the `tracks to deine substantially definite points at which the'tracks are confined to engagement with the ground when the tracks are elevated, this characteristic being of especial advantage when the rear of the truck frames are tilted -then eii'ectively to enable the vehicle to make a sharp turn. i

While I have herein shown and particu-A larly described the preferred vembodiment of'my invention I do not wish to be limited to the precise details of construction shown as changes may readily be made without departing from the spirit of the invention.

Having thus described myl invention I 125 claim as new and desire to secure by Letters 'Patent the following A vehicle including a vehicle body; end-` less tracks, formed of links,V upon 'which wheels of the vehicle may turn; two wheels 130 foi each track and :wout which sufi ack o the vehice, said structures coperatng passes; im v:a,mes upon which are ma'unwid, h@ forward. track Wheels in defining o @ruck :fz-muss; m. means isf musing and mamtammg eevzzd the rem ends 0i* truck frames and h@ mlers mounte may@ JOHN O. MORRIS. 

